a solid round bar with diameter of 2 in has a groove cut to a diameter of 1.8 in, with a radius of 0.1 in. the bar is not rotating. the bar is loaded with a repeated bending load that causes the bending moment at the groove to fluctuate between 0 and 25 000 lbf in. the bar is hot-rolled aisi 1095, but the groove has been machined. a fully corrected endurance limit is